System and method for target substance identification

ABSTRACT

Systems and techniques for detecting a target substance, such as THC, in a breath constituent sample are provided.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No. 15/943,123, filed on Apr. 2, 2018, and titled “SYSTEM AND METHOD FOR TARGET SUBSTANCE IDENTIFICATION,” which issued on Mar. 23, 2021, as U.S. Pat. No. 10,955,428 and which is a continuation of U.S. patent application Ser. No. 15/217,264, filed on Jul. 22, 2016, and titled “SYSTEM AND METHOD FOR TARGET SUBSTANCE IDENTIFICATION,” which issued as U.S. Pat. No. 9,933,445, on Apr. 3, 2018, which itself claims benefit of priority under 35 U.S.C. § 119(e) to U.S. Provisional Patent Application No. 62/337,286, filed May 16, 2016, and titled “BREATH COLLECTOR MODULE,” U.S. Provisional Patent Application No. 62/351,858, filed Jun. 17, 2016, and titled “COMPOSITIONS AND METHODS FOR DETECTION OF TARGET CONSTITUENT IN EXHALED BREATH,” and U.S. Provisional Patent Application No. 62/351,821, filed Jun. 17, 2016, and titled “SYSTEM AND METHOD FOR TARGET SUBSTANCE IDENTIFICATION”; this application is also related to U.S. patent application Ser. No. 15/217,151, filed Jul. 22, 2016, and titled “COMPOSITIONS AND METHODS FOR DETECTION OF TARGET CONSTITUENT IN EXHALED BREATH,” which also claims benefit of priority to U.S. Provisional Patent Application No. 62/351,858, filed Jun. 17, 2016; this application is also related to U.S. patent application Ser. No. 14/997,405, titled “METHOD, DEVICE AND SYSTEM FOR TARGET SUBSTANCE DETECTION” and filed Jan. 15, 2016, which claims priority benefit under 35 U.S.C. § 119(e) to U.S. Provisional Application Nos. 62/104,813, filed Jan. 18, 2015, and 62/107,331, filed Jan. 23, 2015, both of which are titled “METHOD, DEVICE AND SYSTEM FOR TARGET SUBSTANCE DETECTION,” as well as to U.S. Provisional Application No. 62/277,854, filed Jan. 12, 2016, and titled “PORTABLE, HAND-HELD INSTRUMENT FOR DETECTION AND QUANTIFICATION OF CANNABINOIDS AND ALCOHOL IN EXHALED HUMAN BREATH”; all of these applications are hereby incorporated by reference herein in their entireties.

FIELD OF THE INVENTION

The present disclosure relates generally to analytical measurement devices, and more specifically to devices capable of measuring substances in exhaled human breath.

BACKGROUND

With legalization of marijuana expanding and the risk of marijuana-associated impaired driving increasing, it is anticipated by the present inventors that there will be an increased need for portable and accurate measurement devices for quantifying levels of cannabinoid compounds, such as tetrahydrocannabinol (THC), that are present in a person's breath, e.g., such as during a traffic stop for suspected driving-under-the-influence. THC detection poses significant challenges since the amounts of THC that may be present in an exhaled breath are quite minute—much more so than is the case with alcohol. Furthermore, THC detection in human breath is generally the only reliable way to determine if a suspected marijuana user is under the influence. Unlike with alcohol, which the body can purge in relatively short order, e.g., less than a day, THC compounds may be present in a person's body long after they are no longer under the influence of the THC. Thus, detection of THC via blood or urine sample may result in false positives. Testing for THC in breath at the roadside would be convenient, non-invasive, and leverages the wide acceptance of administering a breath test at the roadside, as is commonly employed for alcohol.

SUMMARY

Details of one or more implementations of the subject matter described in this specification are set forth in the accompanying drawings and the description below. Other features, aspects, and advantages will become apparent from the description, the drawings, and the claims.

In some implementations, a tetrahydrocannabinol (THC) detection system is provided that includes an elution port, a sample reservoir containing a sample solvent, an indicator chamber containing an indicator, a solvent reservoir, a buffer reservoir containing a basic buffer, an optical measurement chamber, and a plurality of valves that are configured to control fluid flow from or to the elution port, the sample reservoir, the indicator chamber, the solvent reservoir, and the optical measurement chamber. The plurality of valves may be arranged such that fluid flow between such components is controllable to permit a breath constituent sample to be conveyed from the elution port to the sample reservoir, permit at least a portion of the basic buffer to be combined with the breath constituent sample, permit at least a first portion of the indicator to be combined with the breath constituent sample to form a sample adduct with any THC that is present in the breath constituent sample, permit at least a first portion of the solvent to be combined with the sample adduct, and permit the combined sample adduct and solvent to be delivered to the optical measurement chamber.

In some implementations, the solvent in the solvent reservoir may be a mixture of methyl tertiary butyl ether and heptane.

In some implementations of the THC detection system, the system may further include a controller having one or more processors and a memory. The one or more processors may be communicatively connected with the memory, and the memory may store computer-executable instructions for controlling the one or more processors to control the plurality of valves to facilitate the conveying of the breath constituent sample from the elution port to the sample reservoir, the combining of the at least a first portion of the indicator with the breath constituent sample to form the sample adduct, the combining of the at least a first portion of the solvent with the sample adduct, and the delivering of the combined sample adduct and solvent to the optical measurement chamber.

In some implementations of the THC detection system, the elution port, the sample reservoir, the indicator chamber, the solvent reservoir, the optical measurement chamber, and the plurality of valves may be located in a common cartridge that is configured to be inserted into an analysis unit having an optical sensor system configured to obtain luminescence readings from the combined sample adduct and solvent from the optical measurement chamber. In some such implementations of the THC detection system, the system may further include an analysis station that is configured to receive the common cartridge, includes the optical sensor system, and includes actuators configured to independently actuate the sample reservoir and the solvent reservoir so as to drive fluids into and out of the sample reservoir and the solvent reservoir.

In some implementations of the THC detection system, the plurality of valves may be further arranged such that fluid flow between the components is controllable to deliver an eluent from the sample reservoir to the elution port before the breath constituent sample is conveyed to the sample reservoir. In some such implementations, the system may further include a handheld breath capture module configured to removably connect with the elution port, the handheld breath capture module including a mouthpiece, a saliva trap, and a catch media located between the saliva trap and the elution port when the handheld breath capture module is connected with the elution port. In some further such implementations, the catch media may be silica microbeads having nominal maximum dimensions of between 400 μm and 1500 μm, glass wool, activated charcoal granules, glass wool, layered mesh screens, or frits.

In some implementations of the THC detection system, the system may further include a controller having one or more processors and a memory. The one or more processors may be communicatively connected with the memory, and the memory may store computer-executable instructions for controlling the one or more processors to control the plurality of valves to facilitate the delivering of the eluent from the sample reservoir to the elution port, the conveying of the breath constituent sample from the elution port to the sample reservoir, the combining of the at least a first portion of the indicator with the breath constituent sample to form the sample adduct, the combining of the at least a first portion of the solvent with the sample adduct, and the delivering of the combined sample adduct and solvent to the optical measurement chamber.

In some implementations of the THC detection system, the system may further include an activation cell, and the plurality of valves may be further arranged such that fluid flow between the components is controllable to permit the combined sample adduct and solvent to be delivered to the activation cell prior to delivering the combined sample adduct and solvent to the optical measurement chamber.

In some implementations of the THC detection system, the system may further include a first calibration sample reservoir and a second calibration sample reservoir. In such implementations, the plurality of valves may be further arranged such that fluid flow between the components is controllable to permit at least a second portion of the indicator from the indicator chamber to be combined with a first calibration sample in the first calibration sample reservoir to form a first calibration sample adduct with any THC that is present in the first calibration sample, permit at least a second portion of the solvent to be combined with the first calibration sample adduct, permit the combined first calibration sample adduct and solvent to be delivered to the optical measurement chamber, permit at least a third portion of the indicator from the indicator chamber to be combined with a second calibration sample in the second calibration sample reservoir to form a second calibration sample adduct with any THC that is present in the second calibration sample, permit at least a third portion of the solvent to be combined with the second calibration sample adduct, and permit the combined second calibration sample adduct and solvent to be delivered to the optical measurement chamber. In some such implementations, the first calibration sample may contain no THC and the second calibration sample may contain a known amount of THC. In some alternative such implementations, the first calibration sample may contain a first known amount of THC and the second calibration sample may contain a second known amount of THC that is greater than the first known amount of THC.

In some implementations of the system, the system may further include a controller having one or more processors and a memory. In such implementations, the one or more processors may be communicatively connected with the memory and the memory may store computer-executable instructions for controlling the one or more processors to control the plurality of valves to facilitate the delivering of the eluent from the sample reservoir to the elution port, the conveying of the breath constituent sample from the elution port to the sample reservoir, the combining of the at least a first portion of the indicator with the breath constituent sample to form the sample adduct, the combining of the at least a first portion of the solvent with the sample adduct, the delivering of the combined sample adduct and solvent to the optical measurement chamber, the combining of the at least a second portion of the indicator with the first calibration sample to form the first calibration sample adduct, the combining of the at least a second portion of the solvent with the first calibration sample adduct, the delivering of the combined first calibration sample adduct and solvent to the optical measurement chamber, the combining of the at least a third portion of the indicator with the second calibration sample to form the second calibration sample adduct, the combining of the at least a third portion of the solvent with the second calibration sample adduct, and the delivering of the combined second calibration sample adduct and solvent to the optical measurement chamber.

In some such implementations, the THC detection system may further include a first activation cell and a second activation cell, and the plurality of valves may be further arranged such that fluid flow between the components is controllable to permit the combined sample adduct and solvent to be introduced into the first activation cell prior to delivering the combined sample adduct and solvent to the optical measurement chamber and permit the combined second calibration sample adduct and solvent to be delivered to the second activation cell prior to delivering the combined second calibration sample adduct and solvent to the optical measurement chamber.

In some implementations of the THC detection system, the system may further include an indicator solvent reservoir containing an indicator solvent. In such implementations, the indicator chamber may include a granular or powder indicator and the plurality of valves may be further arranged such that fluid flow between the components is controllable to permit the indicator solvent in the indicator solvent reservoir to be delivered to the indicator chamber in order to mix the indicator solvent with the granular or powder indicator to form the indicator. In some such implementations, the granular or powder indicator may include a functionalized fluorophore. In some further such implementations, the fluorophore may be a rhodamine, and in some specific such implementations, the fluorophore may be rhodamine 123.

In some implementations of the THC detection system, the indicator solvent may be hydrochloric acid.

In some implementations of the THC detection system, the indicator may be a diazo-functionalized reactant.

In some implementations of the THC detection system, the system may further include a controller having one or more processors and a memory. The one or more processors may be communicatively connected with the memory and the memory may store computer-executable instructions for controlling the one or more processors to control the plurality of valves to facilitate: the conveying of the breath constituent sample from the elution port to the sample reservoir, the delivering of the indicator solvent to the indicator chamber to form the indicator, the combining of the at least a first portion of the indicator with the breath constituent sample to form the sample adduct, the combining of the at least a first portion of the solvent with the sample adduct, and the delivering of the combined sample adduct and solvent to the optical measurement chamber.

In some implementations of the THC detection system, the system may further include a cleaning agent reservoir and the plurality of valves may be further arranged such that fluid flow between the components is controllable to permit a cleaning agent in the cleaning agent reservoir to be delivered to the optical measurement chamber. In some such implementations, the cleaning agent may be either ethanol or acetonitrile.

In some implementations of the THC detection system, the system may further include a mixing chamber and the plurality of valves may be further arranged such that fluid flow between the components is controllable to permit the sample adduct and the at least a first portion of the solvent to be delivered to the mixing chamber and then from the mixing chamber to the optical measurement chamber. In some such implementations of the system, the mixing chamber may include a short siphon and a long siphon that is longer than the short siphon, and the plurality of valves may be further arranged such that fluid flow between the components is controllable to permit the sample adduct and the at least a first portion of the solvent to be delivered to the mixing chamber via the long siphon and permit the combined sample adduct and solvent to be removed from the mixing chamber via the short siphon for delivery to the optical measurement chamber.

In some further such implementations of the system, the system may also include a controller having one or more processors and a memory. The one or more processors may be communicatively connected with the memory and the memory may store computer-executable instructions for controlling the one or more processors to control the plurality of valves to facilitate: the conveying of the breath constituent sample from the elution port to the sample reservoir, the combining of the at least a first portion of the indicator with the breath constituent sample to form the sample adduct, the combining of at least the first portion of the solvent with the sample adduct, the delivering of the sample adduct and the at least a first portion of the solvent to the mixing chamber, and the delivering of the combined sample adduct and solvent to the optical measurement chamber.

In some implementations of the THC detection system, the system may further include a pump and the plurality of valves may be further arranged such that fluid flow between the components is controllable to permit pressure from the pump to be applied to the mixing chamber so as to force the combined sample adduct and solvent into the short siphon.

The above implementations are only some of the implementations discussed herein, and do not constitute an exhaustive list of implementations consistent with the scope of this disclosure. Further implementations will be evident from the more detailed discussion provided by the entirety of this disclosure.

BRIEF DESCRIPTION OF THE DRAWINGS

The various implementations disclosed herein are illustrated by way of example, and not by way of limitation, in the figures of the accompanying drawings, in which like reference numerals refer to similar elements.

FIG. 1 depicts a schematic of an example target substance analysis system.

FIG. 2 depicts the example target substance analysis system of FIG. 1 during delivery of an eluent from a sample reservoir.

FIG. 3 depicts the example target substance analysis system of FIG. 1 during recovery of an eluted breath constituent sample.

FIG. 4 depicts the example target substance analysis system of FIG. 1 during delivery of an indicator solvent to an indicator chamber.

FIG. 5 depicts the example target substance analysis system of FIG. 1 during recovery of a liquid indicator from the indicator chamber.

FIG. 6 depicts the example target substance analysis system of FIG. 1 during delivery of a basic buffer to the eluted breath constituent sample.

FIG. 7 depicts the example target substance analysis system of FIG. 1 during delivery of the indicator to the breath constituent sample.

FIG. 8 depicts the example target substance analysis system of FIG. 1 during delivery of the indicator to a first calibration sample.

FIG. 9 depicts the example target substance analysis system of FIG. 1 during delivery of the indicator to a second calibration sample.

FIG. 10 depicts the example target substance analysis system of FIG. 1 during delivery of the combined indicator and first calibration sample to a mixing chamber.

FIG. 11 depicts the example target substance analysis system of FIG. 1 during delivery of a solvent to the mixing chamber.

FIG. 12 depicts the example target substance analysis system of FIG. 1 during mixing of solvent and the combined indicator and first calibration sample.

FIG. 13 depicts the example target substance analysis system of FIG. 1 during separation of the mixture in the mixing chamber.

FIG. 14 depicts the example target substance analysis system of FIG. 1 during delivery of a separation layer to an optical measurement chamber.

FIG. 15 depicts the example target substance analysis system of FIG. 1 during optical measurement of the contents of the optical measurement chamber.

FIG. 16 depicts the example target substance analysis system of FIG. 1 during purging of the optical measurement chamber.

FIG. 17 depicts the example target substance analysis system of FIG. 1 during purging of another portion of the analysis system.

FIG. 18 depicts the example target substance analysis system of FIG. 1 during delivery of the combined indicator and sample to the mixing chamber.

FIG. 19 depicts the example target substance analysis system of FIG. 1 during mixing of solvent and the combined indicator and sample.

FIG. 20 depicts the example target substance analysis system of FIG. 1 during delivery of a separation layer from the mixing chamber to a first activation cell.

FIG. 21 depicts the example target substance analysis system of FIG. 1 during delivery of the separation layer in the first activation cell to the optical measurement chamber.

FIG. 22 depicts the example target substance analysis system of FIG. 1 during delivery of the combined indicator and the second calibration sample to the mixing chamber.

FIG. 23 depicts the example target substance analysis system of FIG. 1 during mixing of solvent and the combined indicator and second calibration sample.

FIG. 24 depicts the example target substance analysis system of FIG. 1 during delivery of a separation layer from the mixing chamber to a second activation cell.

FIG. 25 depicts the example target substance analysis system of FIG. 1 during delivery of the separation layer in the second activation cell to the optical measurement chamber.

FIG. 26 depicts a variant of the target substance analysis system of FIG. 1 .

FIG. 27 depicts an isometric view of an example target substance analysis system.

FIG. 28 depicts a base station of the example target substance analysis system without a cartridge or handheld breath collector module installed.

FIG. 29 depicts an isometric cutaway view of an example optical measurement sensor.

FIG. 30 depicts an example cartridge.

FIG. 31 depicts the example cartridge of FIG. 30 with the cover removed to allow the internal components to be more clearly seen.

FIG. 32 depicts the same uncovered view of the example cartridge of FIG. 30 , but with various subassemblies exploded to allow for clearer viewing.

FIGS. 33 and 34 depict section views of an example mixing chamber.

FIG. 35 depicts a section view of an optical measurement chamber.

FIG. 36 depicts a section view of a first activation cell.

FIG. 37 depicts an example handheld breath collector module.

FIG. 38 is a photograph of a prototype cartridge during assembly; this view gives some idea of the nature of the tubing connections between the components.

FIG. 39 is a photograph of a prototype cartridge mounted into a prototype base station.

FIG. 40 is a photograph of another variant of a prototype cartridge with a layout similar to that in FIG. 26 .

FIGS. 41 through 43 are color versions of FIGS. 38 through 40 .

DETAILED DESCRIPTION

The analysis systems discussed herein generally employ a luminescence-based approach to measuring the amount of a target substance, e.g., THC, in a person's breath. At a high level, a desired quantity of a person's breath is flowed through some form of catch media, e.g., such as catch media in a small, portable, hand-held device, and then eluted; the resulting elution is then used as the “unknown” sample in the analysis system, and is subjected to one or more mixing, separation, and/or activation operations prior to being optically evaluated to determine an amount of THC that is present in the sample.

Quantitative detection of THC in human breath is challenging due to the extremely low concentration of THC in human breath and the presence of many common, similarly structured contaminants or chemical interferences. As disclosed herein, breath constituents from one or more (e.g., 1-3) exhalations may be captured with a handheld device for roadside analysis. Any THC in a breath sample taken with the device can be captured by adsorption on a catch medium or catch media. THC adsorbed on the catch medium may be eluted from the capture medium using a polar organic solvent. A basic buffer and an aqueous diazotized fluorophore solution may then be added to the capture solution to form a fluorescent-labeled THC adduct in a sample adduct solution having a basic pH.

After formation of the adduct solution, a nonpolar organic solvent may be added to the sample adduct solution, the resulting mixture vigorously mixed, and the mixture then allowed to separate into polar and nonpolar phase layers. Any fluorescent-labeled THC-adduct will be contained in the nonpolar layer, and thereby isolated by solvent extraction from molecular species that dissolved in polar, but not nonpolar solvents.

Once the sample adduct, if any, is isolated in the nonpolar fraction of the solvent extraction, it can then be detected and quantified by optical techniques, for example measuring the fluorescence of the fluorescent-labeled adduct and determining a quantity of any THC captured from the original breath sample based on the measured fluorescence.

FIG. 1 depicts a schematic of an example target substance analysis system. In FIG. 1 , the example target substance analysis system is configured to facilitate the detection of tetrahydrocannabinol (THC) in a person's breath, thereby allowing for “BREATHALYZER®” type testing for people suspected of being under the influence of THC. As will be appreciated from the following discussion, the detection of THC in a breath sample may involve a number of different steps, and it is to be understood that while these steps are described with respect to a particular embodiment of a THC analysis system, other embodiments falling within the scope of this disclosure may operate differently from the specific examples discussed but may nonetheless still fall within the scope of the disclosure.

In FIG. 1 , the analysis system 100 includes components grouped into three general assemblies: a cartridge 102, a base station 104, and a breath capture module 106. These three assemblies may be interconnected or disconnected during operation to facilitate the analysis of a captured breath constituent sample. It is to be understood that other implementations of the concepts discussed herein may offer similar capabilities, but without one or more of such assemblies (or using similar, but different, assemblies).

In the depicted implementation, components relating to the collection of a breath constituent sample from a subject may be contained in a breath capture module (BCM) 106. Such a BCM may be designed to be relatively lightweight and may have features, such as a catch media 114, that are configured to promote the capture of breath constituents from a person's breath as the person exhales through the BCM 106. The BCM 106 may, for example, be a BCM such as those described in U.S. Patent Application No. 62/337,286, previously incorporated by reference herein. In some implementations, the BCM 106 may include a plurality of microbeads or microspheres, as discussed in U.S. Patent Application No. 62/337,286, that are sandwiched between and retained by two mesh screens. In some such implementations, a woven or fibrous filter media or membrane may be interposed between each mesh screen and the microbeads or microspheres; such a woven or fibrous filter media or membrane may provide further surface area onto which breath constituents may adsorb during sample collection and may enhance the ability of the BCM 106 to capture useful samples. For example, in some implementations, the BCM 106 may include one or more layers of filter media such as TECHNOSTAT® 90 PLUS, which is a meltblown synthetic fiber carried on a spunbond polypropylene backing material. TECHNOSTAT® 90 PLUS is manufactured by Hollingsworth & Vose of East Walpole, Massachusetts, and is distributed in the United States of America by Superior Felt & Filtration of McHenry, Illinois, at the time of this writing. In implementations utilizing TECHNOSTAT® 90 PLUS or a similar filter media, the BCM 106 may, in some instances, omit additional filter media such as microbeads and instead rely on one or more layers of the filter media. In some such implementations, the filter media may be sandwiched between mesh screens to provide support to the filter media and to prevent the filter media from getting dislodged. In other such implementations, the filter media may not be sandwiched between mesh screens but may be clamped in place directly, e.g., about the periphery of the filter media.

The BCM 106 may also include a mouthpiece 108, to allow the person to exhale into the BCM 106, and a saliva trap 110, which may prevent or hinder saliva or spittle from reaching the catch media 114. The BCM may also include electronics (not shown), such as one or more processors and a memory storing instructions for controlling the one or more processors, that may control or monitor operation of the BCM 106 and provide information regarding the progress of the sample collection using the BCM 106. For example, the BCM 106 may include a pressure sensor 112 that has a pressure measurement port that is interposed between the saliva trap 110 and the catch media 114 so as to monitor the pressure downstream of the saliva trap 110 and upstream of the catch media 114. The one or more processors may monitor the data from the pressure sensor and determine therefrom the amount of air that is blown into the mouthpiece 108, through the saliva trap 110, and then delivered to the catch media 114. When the amount of exhaled breath that passes through the BCM 106 exceeds a predetermined amount (as determined from the pressure sensor data, or from another sensor providing similar information), e.g., 3 liters, then the one or more processors may cause a signal to be provided that a sufficient sample has been collected, e.g., the BCM 106 may be caused to emit a “beep” or provide some other sort of indication that a sufficient sample has been collected.

After a breath constituent sample is collected in the BCM 106, the BCM 106 may be connected to the cartridge 102 to allow the breath constituent sample to be drawn out of the BCM 106 and analyzed by the analysis system 100.

The cartridge 102 may include a number of reservoirs that contain various chemicals used in the target substance detection techniques used by the analysis system 100. These reservoirs may be configured to allow the fluids contained in each reservoir to be independently dispensed, as needed, during the analysis process. In some cases, one or more the reservoirs may also be configured to allow fluids outside of the reservoirs to be drawn into the reservoir. In the depicted example analysis system 100, the reservoirs 120 take the form of syringes, each of which is actuated by a corresponding actuator 118. The actuators 118 may be located in the base station 104, which may be a larger unit that includes various “durable” systems or components, e.g., the actuators 118, an optical sensor 152, electronics (not shown), power supply components (not shown), etc. The cartridge, which may include various “consumable” elements, e.g., chemicals used during the analysis, may be removably insertable or connectable with the base station to allow for easy replacement of the consumable elements.

It is to be understood that while syringes and actuators are used in the depicted example system, other fluid storage and dispensing systems may be used in place of, or in addition to, such syringe-based systems. Such alternative implementations are to be understood as also being within the scope of this disclosure.

In the depicted example, each of the reservoirs 120 is connected to a common manifold 128 (which may, for example, be provided by two or more separate manifolds 130 and 132 that are linked together via a tube or other connection so as to form the common manifold 128; this was done to allow commercial off-the-shelf manifolds to be used, and could be avoided by custom-manufacturing a single, integrated manifold). Each such connection of a reservoir 120 to the manifold 128 may include a corresponding valve 122 that may be opened or closed to prevent fluid flow between the corresponding reservoir 120 and the manifold 128. In some instances, there may be an additional diverter or 3-way valve that is also interposed between some of the reservoirs 120 and the manifold 128 to allow the fluid that is stored in such reservoirs to be delivered not only to the manifold 128, but also alternatively to another location. In such scenarios, the functionality of the diverter valve and the shut-off valve may be combined into a single valve structure, e.g., a 3-way valve with an integral shut-off capability.

The common manifold may also be configured to allow fluids from the reservoirs 120 to be directed to one or more downstream components, such as a mixing chamber 136, a first activation cell 142, a second activation cell 144, an optical measurement chamber 146, a waste receptacle 148, or other downstream components.

FIGS. 2 through 25 depict the example analysis system of FIG. 1 during various operational phases, and will be referred to in the following discussion describing the operation of the example analysis system during a typical breath constituent analysis. For clarity, certain conventions are adopted in these Figures. For example, valves are represented by two or three triangles pointing towards a common center point; each triangle may represent a port on the valve—if a triangle is black, this indicates that fluid may flow through the port corresponding to that triangle; if a triangle is white, this indicates that fluid is prevented from flowing through the port corresponding to that triangle. Additionally, white arrows have been overlaid on flow paths to indicate the direction of fluid flow at that point in the analysis process.

In FIG. 2 , the analysis may begin with the collection of the breath constituent sample from the BCM 106. To begin with, the BCM 106 may be connected to an elution port in the cartridge 102 (or a similar port on the base station 104), and an eluent may be delivered from a sample reservoir 120 a to the elution port and thereby to the catch media 114 of the BCM 106. For example, a three-way valve 124 a may be actuated such that the sample reservoir 120 a is in fluidic communication with the catch media 114. A sample actuator 118 a may then be actuated so as to meter out a desired amount of eluent from the sample reservoir 120 a and deliver the metered out amount of eluent to the catch media 114. For example, 250 μL of eluent may be dispensed from the sample reservoir 120 a and delivered to the catch media 114.

The eluent, which may, for example, be ethanol (EtOH), may then be allowed soak the catch media 114, e.g., for approximately 30 seconds, so as to elute any breath constituents that have adsorbed onto the catch media 114 into the eluent. After the catch media 114 has been soaked by the eluent for a sufficiently long enough period of time to result in most of the breath constituents being eluted, the resulting eluent and eluted breath constituents may be withdrawn from the BCM 106 and returned to the sample reservoir 120 a, as shown in FIG. 3 . For example, this may be achieved by causing the sample actuator 118 a to be operated in the reverse manner as it was while delivering the eluent from the sample reservoir 120 a to the catch media 114, e.g., as in FIG. 2 . It is to be understood that, if desired, the eluent may be returned to another reservoir (not pictured) which may be sterile or otherwise uncontaminated after collection—as such a solution would involve further components and complexity for little or no benefit, the implementation described herein returns the eluent and eluted breath constituents to the sample reservoir 120 a to await further processing.

After the elution and collection of the breath constituent sample, the system may be operated so as to add an aqueous diazotized fluorophore solution to the eluted breath constituent sample to produce an adduct with THC molecules that may be in the breath constituent sample. In the present example analysis system, such an aqueous diazotized fluorophore solution may be generated by mixing an indicator solvent with a solid-phase indicator to create the aqueous diazotized fluorophore solution, although it is envisioned that such mixing may be unnecessary if alternative aqueous diazotized fluorophore solutions are used that are stable when in liquid form.

The aqueous diazotized fluorophore solution may be produced just before, during, or just after the elution of the breath constituent sample from the catch media 114. For example, a three-way valve 124 b may be actuated so as to put an indicator solvent reservoir 120 b containing an indicator solvent in fluidic communication with an indicator chamber 126 containing a solid-phase indicator. The indicator solvent reservoir 120 b containing the indicator solvent may be actuated by an indicator solvent actuator 118 b so as to dispense a quantity of the indicator solvent into the indicator chamber 126 that contains the solid-phase indicator, as shown in FIG. 4 . After the indicator solvent has been introduced into the indicator chamber 126, the solid-phase indicator may be allowed to dissolve into the indicator solvent for a long enough interval to produce a desired quantity of liquid-phase indicator.

The indicator solvent may be acidic, e.g., 100 μM hydrochloric acid (HCl), and may be added in sufficient quantity so as to produce enough indicator so as to be able to provide equal doses of indicator to the sample reservoir 120 a and to one or more calibration sample reservoirs (if used). In the example analysis system of FIG. 1 , at least 750 μL of indicator solvent may be added to the solid-phase indicator in the indicator chamber 126 to allow for the later delivery of 250 μL of liquid indicator to each of the three sample reservoirs. After sufficient dissolution time has elapsed, the liquid-phase indicator that is present in the indicator chamber 126 may be returned to the indicator solvent reservoir 120 b, e.g., by actuating the indicator solvent actuator 118 b in a reverse manner from how it was actuated in order to deliver the indicator solvent to the indicator chamber 126, as shown in FIG. 5 . In some implementations, the indicator solvent actuator 118 b may be repeatedly actuated so as to drive the mixture of indicator solvent and solid-phase (or dissolving) indicator into and out of the indicator solvent reservoir 120 b so as to promote better mixing and dissolution between the indicator solvent and the solid-phase indicator.

Once the indicator has been formed and the breath constituent sample collected, the indicator may then be combined with the eluted breath constituent sample, as well as with any calibration samples that may be used in the analysis system, to form a fluorescent-labeled THC adduct that may later be used to determine the amount of THC present in each sample. In the example analysis system, two calibration samples are provided, although similar analysis systems may utilize more or less (or no) calibration samples, depending on the accuracy desired or whether alternative calibration mechanisms are used. In the present example analysis system, a negative calibration sample and a positive calibration sample are both used. The negative calibration sample has no THC present but includes a similar type and quantity of fluid as was used to elute the breath constituent sample, and may be stored, for example, in a first calibration sample reservoir 120 c. Conversely, the positive calibration sample has a known amount of THC present in a similar type and quantity of fluid as was used to elute the breath constituent sample, and may be stored, for example, in a second calibration sample reservoir 120 e. The positive calibration sample may have an amount of THC thought to be slightly higher, e.g., 10% higher, than the amount of THC that could reasonably be expected to be in an eluted breath constituent sample so that the fluorescent response of the breath constituent sample during the analysis is bracketed by the positive and negative calibration samples. However, it is to be understood that other implementations may, for example, include a non-zero negative control (not truly negative) or a positive control that is lower than the expected maximum quantity of THC that could reasonably be expected to be in the eluted breath constituent sample. For example, if the legal framework surrounding marijuana evolves to allow some amount of THC to be present in a person's breath before the person is considered to be “impaired,” then the negative control may be pegged to this lower limit instead of zero.

Fluorescent-labeled THC adducts are stable when in a basic solution, but may rapidly degrade when exposed to an acidic environment. Conversely, the aqueous diazotized fluorophore solution may be stable in an acidic solution, e.g., such as when dissolved in hydrochloric acid. In order to increase the longevity of the THC adducts that may result from mixing of the liquid-phase indicator with the eluted breath constituent sample and/or the calibration samples, the eluted breath constituent sample and the calibration samples may be combined with a basic buffer that may prevent or mitigate the degradation of any THC adducts that are formed when the eluted breath constituent sample and/or the calibration samples are combined with the liquid-phase indicator, e.g., by raising the pH of the eluted breath constituent sample and/or the calibration samples sufficiently high enough that the subsequent addition of an acidic indicator solution to the eluted breath constituent sample and/or the calibration samples does not cause the THC adduct to degrade significantly (or at all).

In the case of the sample reservoir 120 a, the buffer may be added after the elution process has completed and the eluted breath constituent sample has been retrieved from the BCM 106. This prevents the buffer from diluting the eluent, which may potentially reduce its effectiveness in eluting the breath constituents. The amount of buffer used may, in some implementations, be significantly larger than the amount of eluent, e.g., 500 μL of buffer may be added to 250 μL of eluent, so the buffer may be the dominant mixture component after combination. In order to prevent the buffer from potentially hindering the elution of the breath constituents from the BCM 106, the buffer may be added to the sample reservoir 120 a after the breath constituents have already been eluted. For example, a buffer valve 122 d and a sample valve 122 a may be opened, and the 3-way valve 124 a may be actuated to as to place the sample reservoir 120 a into fluidic communication with the manifold 128. The buffer may then be delivered to the sample reservoir 120 a by actuating a buffer actuator 118 d that drives the buffer out of a buffer reservoir 120 d.

In the case of the calibration sample reservoirs, the buffer may be introduced in a similar manner or may, as is the case in this implementation, be pre-loaded into the calibration sample reservoirs during cartridge assembly or preparation.

After the eluted breath constituent sample and/or the calibration samples have been provided with the buffer from the buffer reservoir 120 d, the indicator solution from the indicator reservoir 120 b may be dispensed to the sample reservoir 120 a, the first calibration sample reservoir 120 c, and the second calibration sample reservoir 120 e. The distribution of the indicator to the sample reservoir 120 a, the first calibration sample reservoir 120 c, and the second calibration sample reservoir 120 e may be performed simultaneously or sequentially, e.g., in sequence with each distribution of indicator occurring immediately after (or otherwise very close in time after) the previous distribution of indicator. For example, in FIG. 7 , the 3-way valves 124 a and 124 b and the buffer valve 122 a and an indicator solvent valve 122 b have been actuated so as to put the sample reservoir 120 a and the indicator solvent reservoir (now containing the liquid indicator solution) 120 b, respectively, in fluidic communication with the manifold 128, thus allowing liquid-phase indicator to be pushed out of the indicator solvent reservoir 120 b by the actuator 118 b and into the sample reservoir 120 a. Similarly, the indicator solvent valve 122 b and the first calibration sample valve 122 c may both be opened (and the other valves 122 on the manifold 128 closed) to put the indicator solvent reservoir 120 b in fluidic communication with the first calibration sample reservoir 120 c via the manifold 128, as shown in FIG. 8 . A similar quantity of liquid indicator may then be delivered to the first calibration sample reservoir 120 c by actuating the indicator solvent actuator 118 b. The second calibration sample reservoir 120 e may also be provided with liquid indicator in a similar manner, e.g., by opening the indicator solvent valve 122 b and a second calibration sample valve 122 e (and closing the other valves on the manifold 128), as shown in FIG. 9 , and driving the liquid indicator from the indicator solvent reservoir into the second calibration sample reservoir 120 e using the solvent indicator actuator 118 b.

Once the liquid indicator has been added to the eluted sample in the sample reservoir 120 a, as well as the first calibration sample reservoir 120 c and the second calibration sample reservoir 120 e, if used, the amount of THC adduct (if any) that is present in each of the samples may be evaluated. In the example implementation, this occurs in a serial fashion using a largely common set of components located downstream of the manifold 128; these components are washed in between analysis runs in order to prevent cross-contamination of the samples. In other implementations, separate, parallel downstream systems may be used instead, thereby preventing cross-contamination.

During operation of the example analysis system, the first calibration sample valve 122 c and a manifold valve 122 h may both be placed in open states to put the first calibration sample reservoir in fluidic communication with the manifold 128 and, via the manifold 128, a mixing chamber 136. This assumes that the first calibration sample is used; in implementations where such a calibration sample is not used, this portion of the process may be omitted. The first calibration sample, which is a negative calibration sample having no adduct in this case (since there is no THC in it), may then be delivered from the first calibration sample reservoir 120 c to the mixing chamber 136 by actuating the first calibration sample actuator 118 c, e.g., such as is shown in FIG. 10 . Subsequent to the introduction of the first calibration sample to the mixing chamber, the first calibration sample valve 122 c may be closed and a solvent valve 122 f may be opened to put a solvent reservoir 120 f into fluidic communication with the mixing chamber 136 via the manifold 128. A solvent actuator 118 f may be actuated to cause the solvent reservoir 120 f to dispense a solvent within the solvent reservoir 120 f into the mixing chamber 136 via the manifold 128, as is shown in FIG. 11 . The solvent, for example, may be a mixture of methyl tertiary butyl ether (MTBE) and heptane or a similar solvent. In some implementations, the delivery of the solvent and the sample (be it a calibration sample or the breath constituent sample) to the mixing chamber 136 may be done in alternating, piecemeal fashion so as to preliminarily mix the two fluids more effectively.

The mixing chamber 136 may serve a two-fold purpose—it may act as a temporary holding area or reservoir for the current sample in which mixing with the solvent may occur and it may also be used as a vessel in which polar/non-polar phase separation may be used in order to separate out a non-polar layer containing the THC adduct from a polar layer of the mixture. The mixing chamber may have multiple inlets into the chamber, e.g., a long siphon 140, a short siphon 138, and, in some cases, a pressurization inlet (not labeled, but connected to 3-way valve 124 c). The long siphon 140 may extend to the bottom of the mixing chamber 136 such that the mixing chamber 136 may be completely drained by drawing whatever fluids are within the mixing chamber 136 out through the long siphon 140. The short siphon 138, however, may only extend partway down the mixing chamber 136—the length of the short siphon 138 may be designed such that the short siphon 138 extends nearly to the bottom (but not past the bottom) of the separation layer containing the THC adduct after separation has occurred. This allows the short siphon 138 to be used to siphon off the THC adduct after separation for further processing.

After the combined first calibration sample and liquid indicator and the solvent are both delivered to the mixing chamber 136, the delivered mixture may be withdrawn and re-introduced into the mixing chamber 136 multiple times, e.g., by reciprocating the first calibration sample actuator 118 c multiple times, thereby drawing the mixture back into the first calibration sample reservoir 120 c and then re-delivering it to the mixing chamber 136 repeatedly, e.g., such as is shown in FIG. 12 , which may agitate the mixture and further promote thorough and complete mixing of the solvent with the sample. After such mixing, the mixed solution may be allowed to rest within the mixing chamber 136 so that the mixed solution may separate out into polar and non-polar phases, e.g., such as is shown in FIG. 13 .

Once the adduct/solvent/indicator solution has separated in the mixing chamber 136, the separated THC adduct may be delivered to the optical measurement chamber 146, as shown in FIG. 14 . For example, 3-way valves 124 d, 124 e, and 124 f may all be set so as to put the mixing chamber 136 in fluidic communication with the optical measurement chamber 146. Another 3-way valve 124 c may be actuated so as to put an air pump 154 in fluidic communication with the mixing chamber 136; when the air pump 154 is actuated, the resulting pressure increase in the mixing chamber 136 may drive the separated THC adduct into the short siphon 138 and then into the optical measurement chamber 146.

After the first calibration sample is delivered to the optical measurement chamber 146, the first calibration sample may be optically measured to determine an amount of THC adduct, and thus an amount of THC, that is present in the first calibration sample, e.g., such as is shown in FIG. 15 . Such optical measurement may be made by optically stimulating the adduct using light having a first set of wavelengths and then measuring the amount of light having a second set of wavelengths that is then emitted by the THC adduct in the sample in response to such optical stimulation.

Such optical measurement readings may involve a multi-step process. To begin with, the temperature of the optical sensor 152 may be measured for a brief period of time, e.g., 100 ms, and then an optical measurement may be obtained without any illumination of the sample in the optical measurement chamber 146, e.g., for a 100 ms period. The temperature reading may be used to assist in calibrating the output of the optical sensor 152, if necessary (for example, photosensor output voltage may depend on both photosensor temperature and the amount of light that is detected). Subsequent to such a “dark” reading, a “light” reading may be obtained, e.g., one in which the sample is illuminated by the optical source that is used. Again, this may be for a period of time, e.g., 100 ms. The “dark” reading, e.g., the average “dark” reading, may be subtracted from the “light” reading, e.g., the average “light” reading, in order to compensate for any noise-related effects that may affect the results.

In this example, the first calibration sample is a true negative sample, i.e., there is no THC present (and thus no adduct will be formed). Thus, the optical measurement will generally result in a reading of zero, although there may be some low-level luminescence at the frequencies of interest due, for example, to potential contaminants or other sources of light in the sample solution. If present, these low-level luminescence readings may serve as a baseline of what a “zero” reading should correspond to.

After the optical measurement has been obtained, the measured first calibration sample may be delivered from the optical measurement chamber 146 to a waste reservoir 148, as shown in FIG. 16 . In this particular implementation, such a purge operation may be performed by adjusting 3-way valves 124 c, 124 d, and 124 e such that the air pump 154 is in fluidic communication with the optical measurement chamber 146. Once such a fluidic connection has been made, the air pump 154 may be actuated so as to apply positive pressure to the optical measurement chamber 146, thereby driving the first calibration sample out of the optical measurement chamber 146 and into the waste reservoir 148. After the optical measurement chamber 146 has been purged, the mixing chamber 136 and the manifold 128 may be purged in a similar manner, such as is shown in FIG. 17 . In this case, the three-way valve 124 d may be actuated so as to divert air flow from the air pump 154 to the mixing chamber 136 via the short siphon 138, and the manifold valve 122 h and a manifold waste valve 122 i may be actuated so as to place the mixing chamber 136 in fluidic communication with the waste reservoir 148. The resulting air pressure may force the fluids in the mixing chamber 136 into the long siphon 140, thereby driving such fluids back through the manifold 128 and into the waste reservoir 148; a vent 150 may allow the air that is used for such purposes to escape while keeping the used sample in the waste reservoir 148.

After the first calibration sample solution has been purged from the optical measurement chamber 146, the manifold 128, the mixing chamber 136, the optical measurement chamber 146, and any other components that came into contact with the first calibration sample may be washed with a cleaning agent delivered from a cleaning agent reservoir 120 g. Such cleaning may be accomplished by opening a cleaning agent valve 122 g and then driving a cleaning agent out of the cleaning agent reservoir 120 g using a cleaning agent actuator 118 g. The various valves in the analysis system 100 may be actuated so as to route the cleaning agent through the various components with which the first calibration sample came into contact and then ultimately to the waste reservoir. Such routing may be similar to the manner in which the air from the air pump 154 was routed through the analysis system 100, e.g., such as depicted in FIGS. 16 and 17 . After the cleaning agent is routed through the analysis system 100, the cleaned components of the analysis system 100 may be dried by flowing air from the air pump 154 along the same flow paths.

This same process, e.g., the steps depicted in FIGS. 10 through 17 (and the purge and cleaning steps), may be repeated, with some slight differences, for the eluted breath constituent sample and well as for the second calibration sample. Such further processing is discussed below.

After the optical measurement chamber 146 and the mixing chamber 136 are cleaned, the combined eluted breath constituent sample and liquid indicator may be delivered to the mixing chamber 136 from the sample reservoir 120 a, e.g., by opening the sample valve 122 a and the manifold valve 122 h and actuating the sample actuator 118 a (with the 3-way valve 124 a actuated so as to place the sample reservoir 120 a and the manifold 128 into fluidic communication. Thus, the combined eluted breath constituent sample and liquid indicator may be delivered to the mixing chamber 136, as shown in FIG. 18 .

Once the combined eluted breath constituent sample and liquid indicator have been delivered to the mixing chamber 136, the solvent from the solvent reservoir 120 f may be delivered to the mixing chamber, essentially repeating the process depicted in FIG. 11 . Once the solvent has been delivered to the mixing chamber 136, the solvent and the combined eluted breath constituent sample and liquid indicator may be mixed by reciprocating the sample actuator 118 a to repeatedly draw the fluid in the mixing chamber 136 in and out of the sample reservoir 120 a as shown in FIG. 19 , similar to how the first calibration sample was mixed in FIG. 12 .

Once the mixing of the solvent and the combined eluted breath constituent sample and liquid indicator has been completed, the mixture may be allowed to separate, similar to the separation depicted in FIG. 13 . Once the mixture has separated, the sample THC adduct may be siphoned off through the short siphon 138, e.g., by pressurizing the mixing chamber using the air pump 154. The valves 124 d and 124 e may be actuated such that the sample THC adduct is conveyed to the first activation cell 142, as shown in FIG. 20 . The first activation cell 142 may be configured to activate the sample THC adduct, i.e., cause the THC adduct to transition to a state in which it is photo-reactive so that it will luminesce when stimulated with a particular wavelength or wavelengths of light. In some implementations, the first activation cell 142 may be coated with a hydrophobic coating or other coating that interacts with the sample THC adduct in order to activate it. In some implementations, the first activation cell may be a pipette tip produced using StarLab International GmbH's REPEL POLYMER TECHNOLOGY (RPT), (examples of such pipette tips are, for example, the “TIPONE® RPT” sold by USA Scientific, and, more specifically, the 1000 μL XL TIPONE® RPT, part number 1182-1830) , which may be used to produce an optimized conventional polypropylene surface that is extremely hydrophobic; such pipettes have been tested and have proven to be effective at activating THC adducts such as rhodamine-123, as compared with other types of pipette tips that are not able to activate rhodamine-123. In some implementations, there may be one activation cell for each sample that has or may have THC in it, as the process of activating the THC adduct in a given sample may consume the coating or other catalyst that causes the activation.

After the sample THC adduct has been activated in the first activation cell 142, the 3-way valve 124 c may be actuated to put the air pump 154 in fluidic communication with the first activation cell 142 via a pneumatic manifold 134, and the 3-way valves 124 e and 124 d may be actuated so as to put the first activation cell 142 into fluidic communication with the optical measurement chamber 146. The sample THC adduct may then be driven out of the first activation cell 142 by air from the air pump 154, as shown in FIG. 21 , and into the optical measurement cell 146. Once the sample THC adduct is in the optical measurement cell 146, a measurement of the amount of THC adduct that is within the optical measurement cell 146 may be obtained in the same manner as described above with respect to FIG. 15 , and then the analysis system 100 may be purged and cleaned, as discussed above with respect to FIGS. 16 and 17 , and cleaned and dried, as also discussed above.

After the sample THC adduct has been measured and routed to the waste reservoir 148, the second calibration sample may be analyzed. Such analysis may begin with the delivery of the second calibration sample to the mixing chamber 136. For example, a second calibration sample valve 122 e may be opened and the second calibration sample actuator 118 e may be actuated to drive the combined second calibration sample and liquid indicator into the mixing chamber via the long siphon 140.

Once the combined second calibration sample and liquid indicator have been delivered to the mixing chamber 136, the solvent from the solvent reservoir 120 f may be delivered to the mixing chamber as shown in FIG. 22 , essentially repeating the process depicted in FIG. 11 . Once the solvent has been delivered to the mixing chamber 136, the solvent and the combined second calibration sample and liquid indicator may be mixed, as shown in FIG. 23 by reciprocating the second calibration sample actuator 118 e to repeatedly draw the fluid in the mixing chamber 136 in and out of the second calibration sample reservoir 120 a, similar to how the first calibration sample was mixed in FIG. 12 .

Once the mixing of the solvent and the combined second calibration sample and liquid indicator has been completed, the mixture may be allowed to separate, similar to the separation depicted in FIG. 13 . Once the mixture has separated, the second calibration sample THC adduct may be siphoned off through the short siphon 138, e.g., by pressurizing the mixing chamber 136 using the air pump 154. The valves 124 d, 124 e, and 124 f may be actuated such that the second calibration sample THC adduct is conveyed to the second activation cell 144, as shown in FIG. 24 . The second activation cell 144 may be similar to the first activation cell 142 and serve a similar purpose, but with respect to the second calibration sample adduct, i.e., it may be used to activate the second calibration sample adduct.

After the second calibration sample THC adduct has been activated in the second activation cell 144, the 3-way valve 124 c may be actuated to put the air pump 154 in fluidic communication with the first activation cell 142 via a pneumatic manifold 134, and the 3-way valves 124 f, 124 e, and 124 d may be actuated so as to put the second activation cell 144 into fluidic communication with the optical measurement chamber 146. The second calibration sample THC adduct may then be driven out of the second activation cell 144 by air from the air pump 154, as shown in FIG. 25 , and into the optical measurement cell 146. Once the second calibration sample THC adduct is in the optical measurement cell 146, a measurement of the amount of THC adduct that is within the optical measurement cell 146 may be obtained in the same manner as described above with respect to FIG. 15 , and then the analysis system 100 may be purged and cleaned, as discussed above with respect to FIGS. 16 and 17 , and cleaned and dried, as also discussed above.

FIG. 26 depicts a variant of the target substance analysis system of FIG. 1 . In FIG. 26 , a pressure relief valve 178 has been added to the pneumatic manifold 134 to allow pressure that may build up in the activation cells 142 or 144 to be relieved. Such a pressure valve may, for example, activate to release excess pressure when the pressure in the pneumatic manifold 134 exceeds 3 psi above ambient levels.

FIGS. 27 through 37 show various example views of an analysis system, or components thereof, that may be used in the manner described above with respect to FIGS. 1 through 24 . For ease of reference, the components in FIGS. 27 through 37 that correspond to components in FIGS. 1 through 24 are identified by reference numbers having the same last two digits as the corresponding components or element in FIGS. 1 through 24 .

FIG. 27 depicts an isometric view of an example target substance analysis system. The analysis system 200 may include, for example, three separate modules—a base station 204, a cartridge 202, and a handheld breath capture module (BCM) 206. The analysis system may have an exterior housing (not shown) that covers and protects the internal components during use.

FIG. 28 depicts the base station 204 without the cartridge 202 or the handheld BCM 206 installed. As can be seen, the base station may include multiple actuators, such as actuators 218 a through 218 g, which may be used to control how fluids are dispensed from or drawn into the reservoirs that are included in the cartridge 202. In the cartridge 202, the reservoirs that are included are provided in the form of syringes; when the cartridge 202 is installed in the base station 204, each actuator 218 may interface with a plunger of a corresponding syringe and may be actuated so as to move the plunger into or out of the syringe, thus causing fluids to be driven from or sucked into the syringe/reservoir.

The base station may also include an optical measurement sensor 252 that may be configured to obtain luminescence readings from samples that are processed in the cartridge 202. The optical measurement sensor 252, in this implementations, projects an optical beam 264 having a first wavelength range that is selected so as to stimulate emission of light having a second wavelength range from the THC adduct. The emitted light may then be collected by the same optics used for projection and routed to a photodetector in the optical measurement sensor 252 for quantification. FIG. 29 depicts an isometric cutaway view of an example optical measurement sensor 252. A photoemitter 266 may be located so as to direct light along a first axis (the vertical axis with respect to the orientation of FIG. 29 ), and a photodetector 268 may be configured to receive light received along a second axis that is orthogonal to the first axis. A beam splitter 270, e.g., a window that is generally reflective to the first wavelength range but generally transmissive to the second wavelength range, may be located at the intersection of the first axis and the second axis, and may be positioned at a 45° angle to both axes so as to cause light from the photoemitter 266 to be turned 90° and directed out of the optical measurement sensor 252 to form the optical beam 264. At the same time, light that is emitted by the THC adduct in response to stimulation by the light of the first wavelength range may pass through the beam splitter 270 without being reflected and thus be received by the photodetector 268. When measurement of the amount of THC adduct present in a sample is desired, the photoemitter 266 may be turned on so that light of the first wavelength range is emitted to optically pump or stimulate the THC adduct; the light of the second wavelength range that is emitted by the THC adduct in response may then be measured by the photodetector 268, and the intensity of such detected light may be correlated with an amount or concentration of THC adduct (and thus THC) that is present in the sample.

It is to be understood that other types of optical sensors may be used as well, and that some optical sensors may, depending on the particular adduct used, not include a photoemitter, e.g., in implementations where the THC adduct does not require optical pumping in order to emit light.

FIG. 30 depicts an example cartridge 202; the cartridge may have a protective cover (as depicted) and house within it most or all of the “wet” chemistry components that are used in the analysis process. In addition to reservoirs 220 a through 220 g, the cartridge 202 may also include an elution port 256 that may connect with a catch media of the handheld BCM 206. The cartridge 202 may also have mechanical features and electrical connections for interfacing the cartridge 202 with the base station 204 and with the handheld BCM 206.

FIG. 31 depicts the example cartridge 202 with the cover removed to allow the internal components to be more clearly seen. FIG. 32 depicts the same uncovered view of the example cartridge 202, but with various subassemblies exploded to allow for clearer viewing. It is to be understood that the components depicted and described below may be connected together by flexible tubing that provides fluidic connections between the various ports of the components depicted. Such tubing is not depicted in these Figures since the number of tubes and the routing of the tubes would clutter the Figures and impact their clarity. However, it is to be understood that the components depicted in FIGS. 31 and 32 are, in actual practice, connected by such tubing, and that such tubing routing/connections may be consistent with the fluidic connections and routing shown in FIG. 1 .

In FIGS. 31 and 32 , it may be seen that reservoirs 220 are arranged in a row and supported by a common interface block that positions each reservoir 220 in a particular position that allows each 220 to interface with a corresponding one of the actuators 218 when the cartridge 202 is installed in the base station 204. A sample reservoir 2020 a, a solvent reservoir 2020 f, a buffer reservoir 2020 d, a second calibration sample reservoir 2020 e, an indicator solvent reservoir 2020 b, a first calibration sample reservoir 2020 c, and a cleaning agent reservoir 2020 g are depicted. It is to be understood that the order and relative positioning of these reservoirs may be different in various implementations, and that the particular placement of such reservoirs may be selected taking into account various considerations, such as minimization of tubing lengths (to reduce dead volumes), standardization of tubing lengths (to facilitate assembly), etc.

Also visible in FIGS. 31 and 32 are features for interfacing with the handheld BCM 206, e.g., the elution port 256, as well as an electrical interconnect 258 that may allow the cartridge 202 or the base station 204, via the cartridge 202, to communicate with the electronics of the handheld BCM 206.

In the implementation depicted in FIGS. 31 and 32 , the valves 222 are integrated into the manifolds 230 and 232 (rather than being separate, as suggested in FIG. 1 ) to reduce the potential dead volume in the manifold that is formed by the two manifolds 230 and 232. Thus, the manifold 230 may include a buffer valve 222 d, a sample valve 222 a, an indicator solvent valve 222 b, a first calibration sample valve 222 c, and a manifold valve 222 h. Correspondingly, the manifold 232 may include a second calibration sample valve 222 e, a solvent valve 222 f, a cleaning agent valve 222 g, and a manifold waste valve 222 i. 3-way valves 224 a through 224 g may also be included to allow fluid flow to be directed between two different end points (or be received from one of two sources).

The cartridge 202 may also include, for example, an indicator chamber 226 and a waste reservoir 248, as well as a mixing chamber 236, a first activation cell 242 (indicated by outlet port), a second activation cell 244 (indicated by outlet port), and an optical measurement chamber 246 (indicated by outlet port). The mixing chamber may have inlet ports for a short siphon 238, a long siphon 240, and a pressurization port 272.

FIGS. 33 and 34 depict section views of the mixing chamber 236. As can be seen, the long siphon 240 extends nearly all the way to the bottom of the mixing chamber 236, thereby allowing fluids to be delivered to the mixing chamber 236 and completely removed from the mixing chamber 236. The mixing chamber 236 also includes a short siphon 238 that may also be used to introduce fluids to the mixing chamber, if desired, but which may only be used to extract fluids above a predefined level from the mixing chamber, i.e., the short siphon 238 cannot be used to completely empty the mixing chamber 236 (the above discussion assumes that the mixing chamber is used in the orientation depicted with respect to the figure, with the ports located uppermost). The length of the short siphon 238 may be selected such that the end of the short siphon 238 is just above the level at which the THC adduct may be located after separation of the solvent, indicator, THC adduct, buffer, and sample has occurred. Since the amounts of each substance other than the THC adduct are generally known quantities, the length of the short siphon 238 can be set once for a given analysis protocol and then left alone.

FIG. 35 depicts a section view of the optical measurement chamber 246. The optical measurement chamber 246 may be provided, for example, by a cuvette or other optically clear vessel or passage that is suitable for exposing the samples contained within to excitation light and transmitting emitted light out for detection by the optical measurement sensor 252.

FIG. 36 depicts a section view of the first activation cell 242; the second activation cell 244 may be similar. The first activation cell 242, in this case, is a pipette that is held in a housing and that is interfaced with an activation cell fluid port 274 and an activation cell pneumatic port 276. The activation cell fluid port 274 may be connected to the fluid handling systems of the analysis system 200, whereas the activation cell pneumatic port 276 may be connected to a pneumatic system, e.g., such as an air pump 254 (which may, in turn, be connected with a muffler/filter 260, if desired). The air pump 254 may also be connectable with the pressurization port 272 of the mixing chamber, as well as other locations, similar to the implementation shown in FIG. 1 .

FIG. 37 depicts the handheld BCM (a prototype) 206. The handheld BCM 206 may include a saliva trap 210, such as may be used with alcohol breath-analyzer testing units. An example of a suitable saliva trap 210 is the ULTRAP II, described in U.S. Pat. No. 4,292,978, which is sold by Guth Laboratories, Inc. The handheld BCM 206 may also include a mouthpiece 208 (provided, in this case, by one end of the saliva trap 210), as well as catch media 214. Catch media 214 may include a porous media that has a high surface area to volume ratio, and may be as generally described in U.S. Patent Application No. 62/337,286. The handheld BCM 206 may also include on-board electronics 216 that may be configured to monitor how much breath has been breathed through the saliva trap 210 and catch media 214 via a pressure sensor (not shown, but see FIG. 1 ).

FIG. 38 is a photograph of a prototype cartridge during assembly; this view gives some idea of the nature of the tubing connections between the components. FIG. 39 is a photograph of a prototype cartridge mounted into a prototype base station.

The analysis system discussed herein may also include one or more processors, memory, and associated electronics to allow the one or more processors to control the valves, actuators, optical measurement sensor, air pump, and any other controllable elements of the analysis system in order to carry out the operations discussed herein. The memory may store computer-executable instructions for controlling the one or more processors to cause such operations to occur. It is to be understood that the present disclosure relates not only to system and apparatus implementations of the analysis system discussed herein, but also to techniques, methods, and processes for using such analysis systems, as well as to embodiments in which computer-executable instructions for controlling a processor or processors to cause such techniques to be practiced are stored on some form of computer-readable media, e.g., non-transitory, computer-readable media such as a hard disk, solid state drive, or non-volatile flash memory.

In some instances, the one or more processors and memory may include at least one processor and memory that are part of the BCM 106 and/or the cartridge 102 and/or the base station 104. In such cases, there may be processors and memory distributed between two or more of such components, and the components may communicate with one another, either through a wireless communications interface or a wired connection. In some implementations, one or more of the above components may also have a wireless communications interface, e.g., a cellular interface, that allows the one or more processors to wirelessly communicate information to a remote device, e.g., a server. For example, the BCM 106 may include a wireless interface that may transmit information relating to a sample, including, for example, metrics regarding the volume of exhaled breath, the time taken to obtain the sample, the time that the sample was obtained, the location where the sample was obtained (as either entered manually by a user or as obtained automatically, e.g., through use of a GPS receiver located in the BCM 106 or in another nearby piece of equipment, such as a paired smartphone or police car, and/or a picture of the subject providing the sample, e.g., as taken by a paired smartphone or by a camera that may be built in to the BCM 106. The same wireless communications interface, or a different wireless communications interface, may also communicate test results from the analysis system 100 to the same remote device in association with such information or in association with a record identifier linking such further information to previously transmitted information, allowing test results to be associated with a particular subject and sampling time/location.

In one embodiment consistent with the discussion provided above with respect to FIGS. 1 through 25 and FIGS. 27 through 38 , the following quantities and compositions of chemicals may be used (the table below is with reference to the quantities and compositions present prior to analysis):

Reservoir/Chamber Composition Amount Sample Ethanol (EtOH) 250 μL First Calibration EtOH + Buffer 750 μL (250 μL EtOH + Sample 500 μL Buffer) Second Calibration EtOH + THC + 750 μL (250 μL EtOH + Sample Buffer 500 μL Buffer + THC) Buffer NaHCO₃ + Na₂CO₃ 500 μL @ 20 mM NaHCO₃ and 13 mM Na₂CO₃ Solvent Methyl tertiary 3000 μL (2250 μL butyl ether Heptane + 750 μL MTBE) (MTBE) + Heptane Indicator Solvent Hydrochloric acid 1500 μL (HCl, 100 μM concentration) Indicator Chamber Rhodamine + 1 mg camphorsulfonic acid + sodium nitrite Cleaning Agent Acetonitrile or 7500 μL EtOH

In such an embodiment, each of the three samples (the breath constituent sample and the two calibration samples) will be approximately 750 μL prior to the addition of the liquid indicator; the two calibration samples start out at approximately 750 μL (the second calibration sample may be slightly larger in volume due to the additional presence of THC, although this is a negligible contributor to overall volume in view of the other volumes used), and the sample volume may be brought up to 750 μL after the elution is completed and the buffer is added to the eluted sample. After the buffer has been added to each sample, if not already present, 250 μL of liquid indicator may be added to each sample, bringing the overall sample volumes each to 1000 μL. Each combined indicator and sample may then be combined/mixed with 1000 μL of solvent (MTBE+Heptane), and the mixture allowed to separate out. Once separation is complete (or sufficiently complete), approximately 650 μL of the topmost separation layer may be extracted, e.g., by the short siphon, from each sample, activated, if necessary, and then subjected to optical measurement to determine the amount of THC adduct that is present in each sample.

It is to be understood that the above-described system may be implemented in a number of different ways, and that such different implementations are also considered within the scope of this disclosure. For example, calibration samples are used in the example system to provide baseline measurements that may be used to calibrate the unknown sample THC adduct measurement against THC adduct measurements obtained from known quantities of THC. However, such calibration samples (and the equipment for processing them) may be omitted in some cases, e.g., if the accuracy of the THC measurement is not of particular concern (such may be the case where any non-zero amount of THC in a person's breath may be considered to be sufficient grounds for prosecution under a “driving under the influence” statute—the exact amount may be immaterial). Furthermore, the use of a mixing chamber may, in some instances, be optional. For example, mixing may occur in other chambers or vessels of the analysis system instead, such as in the optical measurement chamber—the mixture may be reciprocated in and out of the optical measurement chamber repeatedly, and then allowed to separate within the optical measurement chamber. The optical measurement sensor may, in such implementations, be positioned such that the optically sensitive area of the sensor is aligned with a region of the optical measurement chamber where the THC adduct is expected to separate into a layer, thereby allowing the amount of the THC adduct present to be quantified. In yet further or additional implementations, the activation cells that are used may be omitted and other systems or techniques for activating the fluorophores in the THC adduct may be used. For example, the solution containing the THC adduct may be subjected to a light source of a particular wavelength, an electrical charge, or some other stimulus in order to activate the fluorophore. In the example discussed earlier in this disclosure, the activation of the fluorophores in the THC adduct is achieved by passing the THC adduct into a particular brand and model of pipette that was found, via experimentation, to activate the THC adduct, and then removing the activated THC adduct from the pipette. It will be appreciated that the functionality of the calibration cell may be integrated into other components, such as the optical measurement chamber, thereby obviating the need for a separate activation cell (or cells). For example, if the THC adduct is an adduct that can be activated by passing an electrical charge through it, then electrodes may be placed so as to come into contact with the THC adduct to allow such a charge to be delivered. By way of further example, such electrodes may be placed in the optical measurement chamber so that the THC adduct may be activated within the optical measurement chamber; the optical measurement chamber, in this sense, may be viewed as both the optical measurement chamber and the activation cell. If the activation of the THC adduct involves re-usable components, such as non-consumable electrodes, then separate activation cells for each sample to be activated may be avoided as well, and a single, common activation cell may be used.

It is also to be recognized that the various connections between reservoirs and other components may be made, for example, by way of integrated flow paths in a block of material, e.g., flow paths that are machined or cast in a block of material, thereby eliminating some or all of the tubing connections that are depicted in the photographs. It is also to be understood that the system that is discussed may potentially be implemented on a smaller scale, and that the apparatus depicted in photographs is a test prototype that uses many off-the-shelf parts, such as valves, fittings, reservoirs, etc., and may be refined to be more compact. In such cases, the amounts of the reactants and fluids used may be adjusted to accommodate potentially smaller sample sizes and working volumes. Such refined versions of the apparatus are also considered to be within the scope of this disclosure. 

What is claimed is:
 1. A tetrahydrocannabinol (THC) detection system comprising: a plurality of components, the plurality of components including; one or more chambers to elute and retain a breath constituent sample; one or more indicator chambers containing an indicator; a buffer reservoir containing a basic buffer; a THC reservoir containing a non-zero amount of THC; one or more optical measurement chambers and one or more optical measurement sensors configured to obtain optical measurements from substances in the one or more optical measurement chambers; a plurality of valves that are configured to fluidly connect the plurality of components; and a controller configured to control the plurality of components connected by the plurality of valves to: (i) combine at least a first portion of the basic buffer with the breath constituent sample to form a sample buffer mixture; (ii) combine at least a first portion of the indicator with sample buffer mixture to cause a first sample composition to be formed with any THC that is present in the breath constituent sample; (iii) deliver a first sample composition mixture that includes the first sample composition and the basic buffer to the optical measurement chamber; (iv) combine at least a second portion of indicator with a first amount of THC in the THC reservoir and the basic buffer to form a second sample composition mixture that includes a second sample composition formed by the indicator and the first amount of THC in the THC reservoir; and (v) deliver the second sample composition to the one or more optical measurement chambers.
 2. The THC detection system of claim 1, wherein the indicator comprises a diazotized fluorophore.
 3. The THC detection system of claim 1, wherein the indicator comprises rhodamine.
 4. The THC detection system of claim 2, wherein the indicator comprises rhodamine
 123. 5. The THC detection system of claim 1, further comprising a waste reservoir, wherein the controller is configured to operate one or more of the plurality of valves to: permit at least the first sample composition present in the one or more optical measurement chambers to be delivered to the waste reservoir.
 6. The THC detection system of claim 1, further comprising a cleaning agent reservoir containing a cleaning agent, wherein the controller is configured to operate one or more of the plurality of valves to: permit the cleaning agent to flow through the one or more optical measurement chambers.
 7. The THC detection system of claim 1, wherein the controller is configured to: cause the one or more optical measurement sensors to obtain a first optical measurement from the one or more optical measurement chambers while the first sample composition and the second sample composition are in the one or more optical measurement chambers.
 8. The THC detection system of claim 1, wherein the plurality of components and the plurality of valves are located in a common cartridge; and wherein the common cartridge is configured to be inserted into an analysis unit having the one or more optical measurement sensors configured to obtain luminescence readings from contents of the one or more optical measurement chamber.
 9. The THC detection system of claim 8, further comprising the analysis unit, wherein: the analysis unit is configured to receive the common cartridge.
 10. The THC detection system of claim 1, wherein the indicator includes a functionalized fluorophore.
 11. The THC detection system of claim 10, wherein the functionalized fluorophore is a rhodamine.
 12. The THC detection system of claim 11, wherein the functionalized fluorophore is rhodamine
 123. 13. The THC detection system of claim 1, wherein the indicator is hydrochloric acid.
 14. The THC detection system of claim 1, wherein the indicator is a diazo-functionalized reactant. 